我正在向我的C应用程序中编写一个窗口列表，其中显示了所有顶级窗口，包括阴影，最小化窗口以及其他桌面。我想还原未映射（最小化）的窗口，抬起该窗口，并在选择一个窗口后切换到该窗口的桌面/工作区。
过去，我已经使用Xlib编写了一些东西来完成此任务。我以前使用XSendEvent（）发送类型为_NET_ACTIVE_WINDOW的ClientMessage事件，然后发送XMapRaised（），它运行得很好，但效果并不理想。
我现在正在重写应用程序，并决定将XCB用于窗口列表代码而不是Xlib，并希望创建更好，更高效的实现。 XCB没有等效于XMapRaised（）的功能，而xcb_map_window（）似乎不适合我。我已经找到了大量有关创建和配置新窗口的文档，但是很少用于实现窗口管理器或诸如寻呼机，图标框，任务栏等实用程序的文档。为XCB生成的文档对于哪些内容相当含糊某些功能实际上也是如此。如果有人知道其他有价值的文档，那也很好。
编辑：
我在一个小型实用程序中复制了使用Xlib的一部分旧代码，它实际上完成了我想要的大部分工作，并且似乎可以始终如一地工作：
#include <stdio.h>
#include <stdlib.h>
#include <X11/Xlib.h>
int main(int argc, char **argv) {
Display *display = XOpenDisplay("");
Window rootwin = XDefaultRootWindow(display);
if (argc < 2)
{
printf("usage: %s windowid\n", argv[0]);
return 0;
}
Window window = (Window)strtoul(argv[1], NULL, 0);
printf("switch to window: 0x%lx\n", window);
Atom ActiveWindowAtom = XInternAtom(display, "_NET_ACTIVE_WINDOW", False);
XEvent xev;
xev.xclient.type = ClientMessage;
xev.xclient.window = window;
xev.xclient.message_type = ActiveWindowAtom;
xev.xclient.format = 32;
xev.xclient.data.l[0] = 1U;
xev.xclient.data.l[1] = 1U;
xev.xclient.data.l[2] = 0U;
xev.xclient.data.l[3] = 0U;
xev.xclient.data.l[4] = 0U;
XSendEvent(display, rootwin, False, SubstructureRedirectMask, &xev);
XMapRaised(display, window);
XCloseDisplay(display);
return 0;
}
...然后我解压缩了libX11源，并确认它确实包装了XCB函数，但是包装器使用了一些libX11数据结构而不是XCB中定义的结构，并且使用了太多的宏，因此很难看看到底发生了什么。这是我想出的等效XCB，但似乎没有用：
#include <stdlib.h>
#include <stdio.h>
#include <xcb/xcb.h>
#include "atom_cache.h"
int main(int argc, char **argv) {
xcb_connection_t *connection;
const xcb_setup_t *setup;
xcb_screen_iterator_t screen_iter;
xcb_screen_t *screen;
xcb_window_t rootwin, window;
xcb_void_cookie_t void_cookie;
xcb_client_message_event_t client_message_event;
if (argc < 2)
{
printf("usage: %s windowid\n", argv[0]);
return 0;
}
window = (xcb_window_t)strtoul(argv[1], NULL, 0);
printf("switch to window: 0x%x\n", window);
connection = xcb_connect(NULL, NULL);
setup = xcb_get_setup(connection);
screen_iter = xcb_setup_roots_iterator(setup);
screen = screen_iter.data;
rootwin = screen->root;
// send _net_active_window request
client_message_event.response_type = XCB_CLIENT_MESSAGE;
client_message_event.format = 32;
client_message_event.sequence = 0;
client_message_event.window = window;
client_message_event.type = get_atom(connection, "_NET_ACTIVE_WINDOW");
client_message_event.data.data32[0] = 1UL; // source: 1=application 2=pager
client_message_event.data.data32[1] = 1UL; // timestamp
client_message_event.data.data32[2] = 0UL; // my currently active window?
client_message_event.data.data32[3] = 0UL;
client_message_event.data.data32[4] = 0UL;
void_cookie = xcb_send_event(connection, 1, rootwin, XCB_EVENT_MASK_SUBSTRUCTURE_REDIRECT, (const char *)&client_message_event);
uint32_t values[] = { XCB_STACK_MODE_ABOVE };
xcb_configure_window(connection, window, XCB_CONFIG_WINDOW_STACK_MODE, values);
xcb_map_window(connection, window);
xcb_flush(connection);
xcb_disconnect(connection);
return 0;
}
我仍在设法解决这个问题。
答案 0 :(得分：2)
除了atom_cache中有一个小错误之外，我在问题末尾发布的代码似乎是正确的。我还重新排序了映射窗口，升高窗口并将其设为活动窗口的顺序。我在想，也许我应该将这些解决方案作为xcb示例发布在github上。我已经编写了几个这样的小型cli实用程序，用于与xserver和窗口管理器进行交互，如下所示。也许它们会对其他人有所帮助...
xcb_switchto.c：
#include <stddef.h>
#include <stdlib.h>
#include <stdio.h>
#include <xcb/xcb.h>
int main(int argc, char **argv) {
xcb_connection_t *connection;
xcb_window_t rootwin, window;
xcb_intern_atom_cookie_t atom_cookie;
xcb_intern_atom_reply_t *atom_reply;
xcb_atom_t net_active_window;
xcb_query_tree_cookie_t qtree_cookie;
xcb_query_tree_reply_t *qtree_reply;
xcb_void_cookie_t void_cookie;
xcb_client_message_event_t client_message_event;
xcb_generic_error_t *err;
if (argc < 2)
{
printf("usage: %s windowid\n", argv[0]);
return EXIT_FAILURE;
}
window = (xcb_window_t)strtoul(argv[1], NULL, 0);
printf("switch to window: 0x%x\n", window);
// connect to X server
connection = xcb_connect(NULL, NULL);
// get _NET_ACTIVE_WINDOW atom from X server
atom_cookie = xcb_intern_atom(connection, 0, 18, "_NET_ACTIVE_WINDOW");
if (atom_reply = xcb_intern_atom_reply(connection, atom_cookie, &err)) {
net_active_window = atom_reply->atom;
free(atom_reply);
} else if (err) {
printf("xcb_intern_atom failed with error code %d\n", err->error_code);
return EXIT_FAILURE;
}
// get the window's root window. can there really be more than one?
qtree_cookie = xcb_query_tree(connection, window);
if (qtree_reply = xcb_query_tree_reply(connection, qtree_cookie, &err)) {
rootwin = qtree_reply->root;
} else if (err) {
printf("xcb_query_tree failed with error code %d\n", err->error_code);
return EXIT_FAILURE;
}
// map the window first
xcb_map_window(connection, window);
// now raise (restack) the window
uint32_t values[] = { XCB_STACK_MODE_ABOVE };
xcb_configure_window(connection, window, XCB_CONFIG_WINDOW_STACK_MODE, values);
// and, finally, make it the active window
client_message_event.response_type = XCB_CLIENT_MESSAGE;
client_message_event.format = 32;
client_message_event.sequence = 0;
client_message_event.window = window;
client_message_event.type = net_active_window;
client_message_event.data.data32[0] = 1UL; // source: 1=application 2=pager
client_message_event.data.data32[1] = 1UL; // timestamp
client_message_event.data.data32[2] = 0UL; // currently active window (none)
client_message_event.data.data32[3] = 0UL;
client_message_event.data.data32[4] = 0UL;
void_cookie = xcb_send_event(connection, 1, rootwin, XCB_EVENT_MASK_SUBSTRUCTURE_REDIRECT, (const char *)&client_message_event);
// probably unnecessary
xcb_flush(connection);
// close the connection
xcb_disconnect(connection);
return EXIT_SUCCESS;
}
这里有一个与使用1作为时间戳有关的小问题。在窗口中查询_NET_WM_USER_TIME并使用该值可能会更好，因为有时每次使用1都会将其忽略。我也不确定如何拥有多个根窗口，但我仍然认为最好询问服务器它在哪个根窗口上。也许是非xinerama多头显示器...无论如何，问题解决了。